We report for the first time that the medicinal basidiomycete Lentinula edodes can reduce selenium from inorganic sodium selenite (Se(IV)) and the organoselenium compound 1,5-diphenyl-3-selenopentanedione-1,5 (DAPS-25) to the elemental state, forming spherical nanoparticles. Submerged cultivation of the fungus with sodium selenite or with DAPS-25 produced an intense red coloration of L. edodes mycelial hyphae, indicating accumulation of elemental selenium (Se(0)) in a red modification. Several methods, including transmission electron microscopy (TEM), electron energy loss spectroscopy (EELS), and X-ray fluorescence, were used to show that red Se(0) accumulated intracellularly in the fungal hyphae as electron-dense nanoparticles with a diameter of 180.51±16.82 nm. Under designated cultivation conditions, shiitake did not reduce selenium from sodium selenate (Se(VI)).

The work shows the ability of cultured Basidiomycetes of different taxonomic groups-Lentinus edodes, Pleurotus ostreatus, Ganoderma lucidum, and Grifola frondosa-to recover gold, silver, selenium, and silicon, to elemental state with nanoparticles formation. It examines the effect of these metal and metalloid compounds on the parameters of growth and accumulation of biomass; the optimal cultivation conditions and concentrations of the studied ion-containing compounds for recovery of nanoparticles have been identified. Using the techniques of transmission electron microscopy, dynamic light scattering, X-ray fluorescence and X-ray phase analysis, the degrees of oxidation of the bioreduced elements, the ζ-potential of colloidal solutions uniformity, size, shape, and location of the nanoparticles in the culture fluid, as well as on the surface and the inside of filamentous hyphae have been determined. The study has found the part played by homogeneous chromatographically pure fungal phenol-oxidizing enzymes (laccases, tyrosinases, and Mn-peroxidases) in the recovery mechanism with formation of electrostatically stabilized colloidal solutions. A hypothetical mechanism of gold(III) reduction from HAuCl to gold(0) by phenol oxidases with gold nanoparticles formation of different shapes and sizes has been introduced.

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In connection with the development of modern industry, various means appear to make the life of citizens easier, but this is also used by criminals, modifying, and sometimes leaving some objects in their original state. This is exactly what happened with a new type of ignition means – liquids for lighting firewood and charcoal. Criminals began to use such liquids as a means of crime when setting fire to buildings, structures, cars. The article discusses the physicochemical study of liquids for ignition, sold in the retail trade network as a product for lighting firewood and coal. The wide selection and availability of these objects allows them to be used in the commission of crimes related to arson. The paper considers the range of liquids for ignition with the establishment of their chemical composition, compliance with the composition declared by the manufacturer. A study of eleven samples, often found in the sale of means for ignition, was carried out by gas chromatography using a gas chromatograph Kristall-5000.2 with a flame ionization detector, in addition, the obtained compositions were compared with the manufacturer's declared on the label. It was found that for a number of samples the compositions differ from those declared, for example, the manufacturer declared a mixture of hydrocarbons for the ignition fluid "Lighter", but in fact only methanol, the fluid for ignition "FLAME" declared a mixture of liquid hydrocarbons, and in fact, ethanol, ethyl acetate and diethyl acetate. Thus, the manufacturer, trying to save on ingredients and production methods, uses cheaper and simpler chemical compositions.